<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>217-前瞻.html</title>
</head>
<body>
	
</body>
<script>
	var str = "x1x1x1x1x1x1x1x1";
	var reg = /[a-z](?!\d)/g;

	console.log(str);
	console.log(str.replace(reg,"*"));
</script>
</html>